A recent discovery by University of Arkansas physicists could help researchers establish the existence of quantum spin liquids, a new state of matter. They've been a mystery since they were first proposed in the s. If proven to exist, quantum spin liquids would be a step toward much faster, next-generation quantum computing. Scientists have focused attention and research on the so-called Kitaev-type of spin liquid , named in honor of the Russian scientist, Alexei Kitaev, who first proposed it. In particular, they have looked extensively at two materials—RuCl 3 and Na 2 IrO—as candidates for this type.
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In February, two physicists made a bet on Twitter. Jonathan Dowling, a professor at Louisiana State University, and John Preskill of Caltech wagered a pizza and a beer over whether 10 years from now, someone will have finally invented a machine of longtime physics fantasy: the so-called topological quantum computer.
Preskill bet yes; Dowling bet no. To document the agreement, Dowling typed up the terms in PowerPoint on a clip art parchment backdrop. To most, the subject of their bet is fairly esoteric. But among experts, the building of a topological quantum computer has been a decades-long moon shot, first championed by academics and later taken up by Microsoft, where researchers continue to pursue its development today.
First proposed in by Russian-American physicist Alexei Kitaev, a topological quantum computer represents information in clusters of electrons, known as non-Abelian anyons, inside a material. Theory predicts that these clusters retain a sort of memory of their movement in the material, and the computer could encode information in how they are swapped around. For example, in a pair of anyons, a 0 might be represented as an anyon swapping positions with the one to its right, and a 1 would be swapping the right-side anyon over the left.
Physicists liken swapping two anyons to braiding two strands of hair. The bit of information is represented in which strand is on top in the braid, not in the physical properties of the hair itself. Information encoded this way is also much harder to alter, compared to conventional quantum computing.
Topological quantum computers would be resistant to this type of error. Topological quantum computing exploits the field of geometry known as topology, hence its name. Topologists study properties of objects that stay the same despite deformation. For example, imagine shaping a piece of clay into the shape of a doughnut. You should be able to then smoothly morph that doughnut into the shape of a coffee cup without tearing or re-attaching any clay. Proponents say that such a machine would not suffer the computation errors that plague existing quantum machines—if only physicists could figure out how to build it.
Previously, researchers thought the only way to avoid quantum computing errors was to implement an additional software algorithm that corrected the errors—algorithms that researchers are still working to develop. His machine would use qubits that could be stretched and deformed, so to speak, while retaining their information. Dowling, however, thinks that supporters of the idea need a reality check.
Dowling compares topological quantum computing to string theory, a once-popular approach to unifying all the laws of physics that has since fallen out of favor because its ideas are impossible to test experimentally.
The physicists have known each other for more than two decades, and they have both worked on quantum computing research for even longer. Today, Preskill has become, in a way, the fatherly public face of quantum computing in the US.
In his patient drawl, he often explains quantum concepts to the popular press and nonspecialists at venture capitalist firms. In this de facto role, Preskill has coined catchphrases to make concepts in the math-heavy field easier to grasp.
Both of them have made scientific bets in the past. Preskill won the bet in , when Hawking conceded that yes, information can escape from black holes.
He lost, as came and went—but he says the bet served its purpose. He thinks the bet helped increase research funding for quantum computing. Scientists have long used wagers to spur problem-solving. Kepler lost the bet, but he figured it out five years later. In more recent years, the Long Now Foundation, a nonprofit whose mission is to spur long-term thinking, has established a Long Bet project , a website where people can keep track of wagers, which include ones predicting the world population and the future of slaughterhouses in the UK.
First of all, researchers have not conclusively demonstrated they can actually produce non-Abelian anyons in a material, to make electrons form that distinct pattern. This means they still cannot build the fundamental component of a topological quantum computer. Microsoft, the only big company investing in topological quantum computing, has been working to create non-Abelian anyons in materials since , when the company established Station Q, a research center in Santa Barbara, California, dedicated to this endeavor.
A Microsoft representative declined an interview request for this article. To Dowling, this progress is unpromising. And no announcement ever comes. For him, bets are also a little game he plays with the public. Contributor Twitter. Featured Video. A self-taught artist with a background in physics, David C. Roy has been creating mesmerizing wooden kinetic sculptures for nearly 40 years. Powered solely through mechanical wind-up mechanisms, pieces can run up to 48 hours on a single wind.
Topics quantum computing physics math geometry.
Quantum codes on a lattice with boundary
To the general public, Preskill is probably best known for winning two bets against Stephen Hawking. To readers of Shtetl-Optimized , he might be known for his leadership in quantum information science, his pioneering work in quantum error-correction, his beautiful lecture notes , or even his occasional comments here though these days he has his own group blog and Twitter feed to keep him busy. The symposium was a blast—a chance to hear phenomenal talks, enjoy the California sun, and catch up with old friends like Dave Bacon who stepped down as Pontiff before stepping down as Pontiff was cool. In a polyglot field like quantum information, that alone makes him invaluable. But along with his penetrating insight comes enviable judgment and felicity of expression: unlike some of us me , John always manages to tell the truth without offending his listeners. Also, as I pointed out later, the amount of time John has spent helping me and patiently explaining stuff to me does weigh heavily against his sanity. So I hereby rename John my Lodestar of Awesomeness.
Researchers expand search for new state of matter
In February, two physicists made a bet on Twitter. Jonathan Dowling, a professor at Louisiana State University, and John Preskill of Caltech wagered a pizza and a beer over whether 10 years from now, someone will have finally invented a machine of longtime physics fantasy: the so-called topological quantum computer. Preskill bet yes; Dowling bet no. To document the agreement, Dowling typed up the terms in PowerPoint on a clip art parchment backdrop.
Two Physicists Bet Over a Quantum Computing Moon Shot
Skip to search form Skip to main content You are currently offline. Some features of the site may not work correctly. Bravyi and Alexei Y. Bravyi , Alexei Y. Kitaev Published Mathematics, Physics. A new type of local-check additive quantum code is presented.